This invention relates to wheel lug nut caps and a lug nut and cap combination. In present technology for making and applying wheel lug nut decorative caps, the caps are fastened to the lug nut to be permanently secured thereto by welding, press fitting, or by curling flanges or other segments of the cap into grooves or slots on the lug nut. The cap is made to have an external size which is the finished hexagonal size to be received by a standard lug wrench socket, with the lug nut it covers being a substandard size These "permanently" attached caps can present later problems to the automobile owner. Specifically, if the cap becomes loose or falls off, as frequently occurs, the standard size lug wrench will not fit the substandard nut, making it very difficult to remove the uncapped lug nut. The tendency is for the lug wrench to slip on the nut, thereby rounding the corners of the substandard hex nut and making it even more difficult to remove. When the undersized lug nut is removed, a complete combination nut and cap must be used in its place. Another frequently encountered problem is the galvanic action causing rusting that occurs at the weld joint between the two different materials of the cover and the lug nut.